This invention relates to that field of chromatography which uses thin layer absorbent mediums, such as paper, ion exchange medium, silica gel, glass fiber-silica gel composites or similar material and high speed rotational chromatographic devices utilizing centrifugal force to decrease the amount of time required to separate compounds and increase the volume and the resolution of the compounds so separated. In another aspect, the invention relates to methods for separating compounds using the above device and to apparatus for preparing the absorbent surface on a chromatographic rotor.
Chromatography, generally, relates to the separation of a multi-component mixture by the differential passage of the components of the mixture through an absorbent medium, with the assistance of a solvent, by means of capillary action, gravity, pressure or centrifugal force.
This invention specifically relates to preparative thin layer centrifugal chromatography. Preparative chromatography is concerned with the separation and recovery of a considerable quantity of the components of a mixture. Thin layer chromatography is directed to the use of a thin layer of absorbent medium on a supporting surface of absorb and seaprate a mixture. Centrifugal chromatography relates to the use of strong centrifugal forces to improve the chromatographic separation of the components of a mixture. This invention utilizes all three concepts to provide a novel apparatus and method for producing improved chromatographic results.
The preparative centrifugal chromatography device of this invention is distinguished from analytical centrifugal chromatography devices in that the present invention is directed to separation and recovery of a volume of a mixture component, whereas analytical centrifugal chromatography devices are only concerned with the separation of the mixture on the absorbent medium for analysis there on. Such analytical devices are not presented with the problems of chromatographic collection as in the present invention.
Centrifugal chromatography devices have been known in the prior art. These devices generally consist of rotors or discs upon which a mixture to be separated is placed. The rotor or disc is spun at sufficient speeds to develop centrifugal forces, which assist in separating the applied mixture. The prior art chromatographic devices, however, suffer from several serious disadvantages which impair their use in both commercial and research facilities. Specifically, prior art devices cannot be used in high speed operation wherein significant centrifugal forces are available. Such devices also fail to allow for continuous operation and collection of separated components of a mixture. Additionally, the prior art devices cannot be used to collect appreciable quantities of a separated component or further resolve closely spaced components. The prior art devices have also not dealt effectively with the spattering of separated and eluted components as they fly off the outer edge of the rotor or disc of the chromatographic device. Finally, the prior art devices have not solved the problem of producing uniform absorbent mediums on the chromatographic rotor or disc surface.